Milk or juice bottles, after receiving their contents of fluid, must obtain the protection of a cap screwed securely onto their openings. The placement of the closure on the container must proceed automatically on a large number of bottles moving on a conveyor. It must result in a complete and reliable closure under these automated conditions.
Plastic bottles finding use for milk and other consumable liquids have become thinner in order to reduce the amount of plastic they contain. This will lower the cost to the manufacturer and the bottler. As a consequence, the necks on the bottles have also evolved into a flexible state compared to previous bottles. Applying a cap with a single thread permits the bottle's neck to flex and thus the cap to strip across the threads.
A typical dairy or bottling plant produces many products having different lubricity. Accordingly, merely adjusting the torque of the capping equipment to keep the caps from stripping or becoming loose proves very difficult at best and impossible at worst.
Additionally, current equipment for filling and sealing milk and juice containers generally utilize an extension of the conveyor with a separate additional machine to engage the caps upon the bottles. The equipment requires additional space in the facility and substantial time to properly engage the caps.
Further, the capping equipment utilizes spring-loaded or other mechanical components to hold and twist the caps during their placement on the bottles. The tension of these components changes over time and thus alters their operating characteristics. At times, this may require the stopping of the conveyor lines to readjust the equipment to properly achieve the objectives.
Requiring greater space for the conveyor line or additional equipment increases the cost of the facility as well as the machinery required to initiate the capping process. Suspending operations of the conveyor reduces the utility of the equipment and increase the overall cost of the packaging operations. Accordingly, the search continues for a closure system and applications equipment that will reduce the cost of the operation while at the same time assuring its reliability.